RFR(XS): 8060721: Test runtime/SharedArchiveFile/LimitSharedSizes.java fails in jdk 9 fcs new platforms/compiler

[Calvin Cheung]

While upgrading the compiler on Mac for jdk9, we found this compiler bug 
where it skips the following 2 lines of code in metaspaceShared.cpp when 
optimization is enable (set to -Os) for the fastdebug and product builds.
     strcat(class_list_path_str, os::file_separator());
     strcat(class_list_path_str, "classlist");

The bug is reproducible with Xcode 5.1.1 and 6.1.

A workaround fix is to rewrite an "if" block in the 
MetaspaceShared::preload_and_dump() method.

JBS: https://bugs.openjdk.java.net/browse/JDK-8060721

webrev: http://cr.openjdk.java.net/~ccheung/8060721/webrev/

Testing:
     JPRT
     The affected testcase with product, fastdebug, and debug builds 
built with Xcode 5.1.1 and 6.1.

thanks,
Calvin